Reviews — Chevalier Jervis — On Gold in Nature, 227 



volcanic material at at least four distinct horizons, proving the 

 activity for an immense period of the volcanic forces along this 

 portion of the Pacific margin. Lastly, the sometimes almost insuper- 

 able difficulty of distinguishing between volcanic rocks of different 

 periods when they have suffered a like degree of metamorphism, and 

 the inappropriateness of attempting to apply lithological standards, 

 which have in eastern America or elsewhere been found locally useful 

 in distinguishing between different series of crystalline rocks, in a 

 region characterized by the abundance of easily crystallizable 

 volcanic materials, and in which rocks of as late date as the 

 Carboniferous have suffered a degree of metamorphism comparable 

 to that of the Huronian or altered Qaebec group of Eastern Canada. 



I^E'V^I:EAA7'S. 



I. — On Gold in Nature. [Dell' Oro in Natura., etc.] 'Rj 



Chev. Wm. Jervis, F.G.S., Conservator of the Royal Italian 



Industrial Museum in Turin, etc. Small 8vo. 204 pages, with 



Woodcuts andTables. (Turin, Loescher ; London, TriJbner & Co.) 



rilHIS history of Gold among ancient and modern nations, its 



J geographical distribution, and its geological, mineralogical, and 



economical aspects, is an extension of a part of Prof. Jervis's public 



lectures at the Royal Museum in Turin, on the nature and geological 



bearings of mineral lodes and veins, and of detrital metalliferous 



formations, such as the alluviums and diluviums in which the 



precious metals and gems are so frequently met with. The lectures 



were new for Turin and attracted large audiences ; but the subject 



of Gold alone is treated of in this published portion. 



In writing his monograph on gold, the author has considered this 

 metal historically, economically, and scientifically, but excluding its 

 chemical relationship, as being so well known already. He has 

 given a summary of the history of gold, both as extracted from its 

 original beds, and as employed in society, from the earliest recog- 

 nizable periods (as recorded in '-Genesis"), through the several 

 great nations of antiquity, down to the Fall of the Roman Empire. 

 This summary is clear and useful, and not without some new 

 historical considerations. 



From the period last mentioned down to our own times the 

 production of gold in different countries, and the modes of its 

 occurrence, are treated of in successive chapters — under the follow- 

 ing geographical headings — 1. Japan, China, Siara, Eastern Archi- 

 pelago, and Africa. 2. The lands discovered and opened up by 

 Columbus, Cortez, and Pizarro in the 16th century. 3. Brazil, 

 Uruguay, Guiana, Venezuela, Columbia, Ecuador, Chili, and Bolivia. 

 4. Europe and Asiatic Russia. 5. United States of North America, 

 with California and conterminous territories. 6. Canada, British 

 Columbia, and Nova Scotia. 7. Australia, Tasmania, and New Zealand. 

 Necessarily the geological details and methods of digging, washing, 

 and mining for gold are more fully given for Hungary, Russia 

 and Siberia, California, and Victoria, than for other localities. 



